Problem: Khan.scratchpad.disable(); For every level William completes in his favorite game, he earns $570$ points. William already has $260$ points in the game and wants to end up with at least $3480$ points before he goes to bed. What is the minimum number of complete levels that William needs to complete to reach his goal?
To solve this, let's set up an expression to show how many points William will have after each level. Number of points $=$ $ $ Levels completed $\times$ Points per level $+$ Starting points Since William wants to have at least $3480$ points before going to bed, we can set up an inequality. Number of points $\geq 3480$ Levels completed $\times$ Points per level $+$ Starting points $\geq 3480$ We are solving for the number of levels to be completed, so let the number of levels be represented by the variable $x$ We can now plug in: $x \cdot 570 + 260 \geq 3480$ $ x \cdot 570 \geq 3480 - 260 $ $ x \cdot 570 \geq 3220 $ $x \geq \dfrac{3220}{570} \approx 5.65$ Since William won't get points unless he completes the entire level, we round $5.65$ up to $6$ William must complete at least 6 levels.